The present invention relates to a method and apparatus for placing sutures in soft tissue, and more particularly to methods and devices for arthroscopic repair of a tom rotator cuff.
Suturing of body tissues is a time consuming aspect of most surgical procedures. Many surgical procedures are currently being performed where it is necessary to make a large opening to expose the area of, for instance, the human body that requires surgical repair. There are instruments that are becoming increasingly available that allow the viewing of certain areas of the body through a small puncture wound without exposing the entire body cavity. These viewing instruments, called “endoscopes”, can be used in conjunction with specialized surgical instrumentation to detect, diagnose, and repair areas of the body that were previously only able to be repaired using traditional “open” surgery. In the past, there have been many attempts to simplify the task of driving a needle carrying suture through body tissues to approximate, ligate and fixate them. Many prior disclosures, such as described in U.S. Pat. No. 919,138 to Drake et al, employ a hollow needle driven through the tissue with the suture material passing through the hollow center lumen. The needle is withdrawn, leaving the suture material in place, and the suture is tied, completing the approximation. A limitation of these types of devices is that they are particularly adapted for use in open surgical procedures where there is ample room for the surgeon to manipulate the instrument.
Others have attempted to devise suturing instruments that resemble traditional forceps, such as U.S. Pat. No. 3,946,740 to Bassett. These devices pinch tissue between opposing jaws and pass a needle from one jaw through the tissue to the other jaw. Graspers then pull the needle and suture material through the tissue. A limitation of these designs is that they also are adapted primarily for open surgery, in that they require exposure of the tissues to be sutured in order that the tissue may be grasped or pinched between the jaws of the instrument. This is a severe limitation in the case of endoscopic surgery.
The term “endosurgery” means “endoscopic surgery”, or surgery performed using an endoscope. In conjunction with a video monitor, the endoscope permits the surgeon to remotely visualize the operative site. Operations using an endoscope are significantly less invasive when compared to traditional open surgery. Patients usually return home the next day, or in some cases, the same day of the endosurgical procedure. This is in contrast to standard open surgical procedures where a large incision divides the muscle layers and allows the surgeon to directly visualize the operative site. Patients may stay in the hospital for 5 to 6 days or longer following open surgery. In addition, after endosurgical procedures, patients return to work within a few days versus the traditional 3 to 4 weeks recuperative period at home following open surgery.
Access to the operative site using endosurgical or minimally invasive techniques is accomplished by inserting small tubes, known as trocars, into a body cavity. These trocars have a diameter of, for example, between 3 mm and 30 mm and a length of about 150 mm (6 inches). There have been attempts to devise instruments and methods for suturing within a body cavity through these trocar tubes.
Such an instrument is disclosed by U.S. Pat. No. 4,621,640 to Mulhollan et al. Mulhollan et al. describe an instrument that may be used to hold and drive a needle, but make no provision for retrieval of the needle from the body cavity, nor the completion of the suture by tying. The instrument disclosed by Mulhollan et al. is limited, in that the arc through which the needle must be driven is perpendicular to the axis of the device.
Another such instrument, intended for endoscopic use, is described in U.S. Pat. No. 4,935,027 to Yoon. This instrument uses oppositional hollow needles or tracks pushed through the tissue and adapted to create a tract through which the suture material is pushed. It is not clear how these curved tracks would be adapted to both be able to pierce the tissue planes illustrated, parallel to the tips of the tracks, and be curved toward each other to form the hollow tract.
Yet another instrument and method is shown by Caspari in U.S. Pat. No. 4,923,461 issued May 8, 1990 and U.S. Pat. No. 4,957,498 issued Sep. 18, 1990. The Caspari patents disclose an endoscopic instrument suitable for use through a trocar that resembles the Yoon approach, but with a single hollow needle on one of a set of oppositional jaws. The jaws simultaneously close, grasping the tissue. The jaw opposite the hollow needle has a window through which the hollow needle passes as the jaws close, freeing the lumen of the hollow needle from the tissue. Much like Yoon, a suture or suture snare is pushed down through the lumen and retrieved from the suture site, the jaws released, and the suture pulled back out through the trocar. This device may be used to place simple stitches in tissues that have been mobilized and have an edge accessible to the jaws. A limitation of the device is the manipulation that must be done with the snare if a suture other than a monofilament is used.
Another instrument specifically adapted for the orthopedic surgeon for the repair of a torn anterior cruciate ligament or for meniscal repair is disclosed in U.S. Pat. No. 4,836,205 to Barrett. Barrett combines in a single instrument the functions of grasping the tissue to be sutured and the passing of the needles through that tissue. It is to be understood that this instrument is designed for use specifically under endoscopic view, and through trocars as previously described. A fairly generic endoscopic grasper is disclosed that has been adapted to allow for a hollow lumen from the handle of the grasper down to the distal tip of the grasper jaws. An elongate needle of 8 to 10 inches in length may be passed through this hollow lumen. The needle, being significantly longer than the grasper, is introduced through the handle of the grasper, and may be driven through the tissue being held in the grasping jaws of the device. The needle is then retrieved from the tissue via a trocar port placed substantially opposite the port through which the grasper is introduced. If a mattress stitch is desired, two needles attached to opposite ends of a suture are both passed through the tissue and retrieved. A limitation of this device is that there must be both visual and physical access to both sides of the tissue flap to be sutured. This requires trocars to be placed opposite each other and roughly on a line intercepting the tissue. This is a severe limitation in the instance of shoulder repair, and specifically in repair of the rotator cuff.
Yet another instrument adapted for use in endoscopic procedures is described by Garman et al in U.S. Pat. No. 5,499,991. This instrument has an elongated housing provided with a needle tip and a lateral opening near the sharpened needle tip. A suture engaging hook, typically formed from wire, is extendable through the lateral opening and away from the axis of the elongated housing by virtue of being predisposed to bend away from the axis in order to snare the suture. The hook is situated at the distal end of an elongated flexible support which is pre-formed in order to enable the hook to be laterally displaced from the axis of the needle tip when the support is moved distally relative to the lateral opening. When a suture is engaged by the hook, the hook is retracted proximally in order to place and hold the suture adjacent the lateral opening. The instrument is somewhat limited in the case of rotator cuff repair in that an additional instrument would need to be introduced into the joint to immobilize the tissues sufficiently to allow the needle tip to penetrate the tissues to be sutured. Also, no provision is made for capturing the two ends of a suture to place a mattress stitch, save repeating the prior steps.
A similar instrument is disclosed in U.S. Pat. Nos. 5,312,422 and 5,474,565 issued to Trott. These patents also describe a needle structure adapted for penetration of soft tissues and suture retrieval. A substantially flat suturing needle with a hook feature is illustrated which can engage a suture to an outer housing, thereby presenting a relatively smooth surface at the distal end of the needle to minimize tissue trauma. The limitations mentioned above are evident here as well. The requirement for additional instrumentation to immobilize the tissues, and the lack of provision for a mattress stitch are paramount. There have been other attempts to improve the methods of tissue repair. These include the development of staplers and anchoring devices. In response to some of the aforementioned problems in placing sutures in tissues endoscopically, manufacturers have developed tissue staplers. These devices utilize stainless steel or titanium staples that are constructed much like the staples used to hold papers together. The major disadvantage of these kinds of staplers is that they leave metal in the body. For some tissues this is not a problem, however in some procedures, metal staples left within the tissues can be a major hindrance to the healing process.
Orthopedic surgeons have begun to explore alternatives to the traditional open approach for the many indications requiring reconstruction of some aspect of the shoulder. As they did in adopting minimally invasive approaches to knee repair and reconstruction, the use of either an endoscope or a “mini-open” approach is gaining in popularity with surgeons, patients and third party payers. It is an increasingly common problem for tendons and other soft, connective tissues to tear or to detach from associated bone. One such type of tear or detachment is a “rotator cuff” tear, causing pain and loss of ability to elevate and externally rotate the arm. Complete separation can occur if the shoulder is subjected to gross trauma, but typically, the tear begins as a small lesion, especially in older patients.
Less invasive arthroscopic techniques are beginning to be developed in an effort to address the shortcomings of open surgical repair. Working through small trocar portals that minimize disruption of the deltoid muscle, a few surgeons have been able to reattach the rotator cuff using various bone anchor and suture configurations. The rotator cuff is sutured intracorporeally using instruments and techniques such as the Caspari punch previously described. This creates a simple stitch instead of the more desirable mattress or Mason-Allen stitch. Rather than thread the suture through trans-osseous tunnels which are difficult or impossible to create arthroscopically using current techniques, an anchor is driven into bone at a location appropriate for repair. The repair is completed by tying the cuff down against bone using the anchor and suture.
Early results of less invasive techniques are encouraging, with a substantial reduction in both patient recovery time and discomfort. However, as mentioned, this approach places only one loop of suture in the cuff for each anchor, reducing the fundamnental strength of the repair. The knots in the tendon can be bulky and create a painful impingement of the tendon on the bone. This is because the knots end up on top of the cuff, in the sub-acromial space, and have the opportunity to rub on the acromion as the arm is raised. Because non-absorbable suture materials are used for these types of repairs, the suture and associated knots are not absorbed into the body, and hence provide a constant, painful reminder of their presence. None of the prior art devices are adaptable to effect the placement of a mattress stitch in grasped tissues, nor are they adaptable to place sutures precisely and controllably while making provision for needle retrieval when using endoscopic techniques. None of the prior art devices make it possible to place a mattress stitch into, for example, the supraspinatus tendon utilizing an endoscopic approach.
What is needed, therefore, is a family of novel suturing devices that overcome the above described disadvantages of prior known devices in a simple and economical manner. The devices should be capable of arthroscopically creating a mattress stitch in a tendon to increase the soft tissue pullout strength of the repaired tendon.